To
many truck enthusiasts, one of GMs biggest mistakes was not
outfitting the S-10 and Sonoma line of compact pickup trucks
with a V-8 engine. The idea is not new, and few aftermarket
companies have been successful in installing a small-block
Chevy into earlier models of these pickup trucks. However,
with current emissions regulations and new smog laws, the
idea seemed unfeasible. Yet we consulted with Steve Cole from
The Turbo Shop in Compton California, who is an expert at
GM computer programming and has a vast knowledge of emission
testing procedures, to see if it was possible with current
technology.

To begin,
Cole set out to work with the Pontiac/GMC performance division
and the plans for the truck were set. Pontiac/GMC sent Cole
a '99 Sonoma extended cab, outfitted with a 4.3L V-6 and four-speed
automatic transmission. They also sent a well-abused Pontiac
Firebird that was used for testing at the Arizona Proving
Grounds. Cole had the task of first removing the engine and
transmission from the Sonoma, and swapping them out for the
components from the Firebird. These included the LS-1 V-8
engine and the computer and ignition system, along with the
4L60E automatic trans- mission. Although the LS-1 didn't have
too many test miles on it, Cole freshened up the LS-1 with
a performance- grind camshaft from Competition I Cams and
a set of Lingenfelter CNC- I ported cylinder heads. The result
was 430 hp that would light the rear tires like a smoke bomb.

The installation,
however, was not i so easy. The problems Cole faced in fitting
the LS-1 into the Sonoma were I not out of the ordinary for
earlier model swaps of this nature. Modifications to the truck's
K-member had to be made because the LS-1 oil pan sump was
too large. The pan was swapped out for a truck 5.3L oil pan,
pump, and pickup, and some modifications to the transmission
cross member were also made to fit the 4L60E out of the Fire-
bird. Cole also used the front drive accessories out of a
Corvette, as the alternator, power steering, and other items
are more compact and tuck closer to the engine. This made
it easier to fit the LS-1 into the small engine compartment
of the Sonoma. Cole also had to fabricate an air intake duct,
modifying the factory intake from a Chevy 6.0L Silverado and
outfitting it with a K&N air filter.

The exhaust
system also had to be fabricated. Cole made up a set of headers
that exit into a free-flowing exhaust system and out through
a large exhaust tip. But according to Cole, the hardest part
of the installation was completely rewiring the engine harness
to match the LS-1 computer to the Sonoma's instrument cluster.

Once the
truck was completed, we were anxious to see what it was capable
of. The combination of 430 hp and a lightweight truck prompted
Cole to slightly detune the engine so that it would not sit
on the launch pad and spin the tires all day long. Even so,
we took the truck to Los Angeles County Race- way and managed
to run a corrected time of 12.34 at 113 mph. The rear wheels
spun a bit off the line but also broke loose in second gear,
almost sending Cole into the guardrail on a couple of passes!
We also had the opportunity to test the truck on a 200-foot
skid- pad, where the Chassis Tech and Nitto tire combination
actually showed some impressive cornering abilities-averaging
0.85 g's during our test.

Although
the Sonoma doesn't look or sound menacing, driving it around
town is like driving an old 427 SC Cobra or 427 '69 Corvette.
The only exception is that the idle characteristics of the
engine and its fine-tuning make the truck actually drive somewhat
like a stock Sonoma-until you hammer on the throttle and get
pushed back into your seat. On more than one occasion, we
surprised the hell out of unsuspecting Mustangs, Camaros,
Corvettes, and Porsches. Perhaps what best describes this
truck is that it is a true "sleeper"-a shark of
the street.

Despite
some of the traction problems, Cole mentioned that he built
the same LS-1 engine combination into a Pontiac Firebird,
which then ran in the high 11-second range. Considering the
Sonoma has a factory 3.08-geared rearend, more gearing and
a traction device may make this truck even quicker. The potential
is there and Cole is ready to move forward with the Sonoma
to get it there.

In an
upcoming issue, we'll hook up with Cole again and show how
the engine was shoehorned into this truck, and if it is feasible
for the average truck enthusiast to duplicate it. Furthermore,
we will be working with Cole to upgrade the truck's brakes,
rear end, interior, and other components as this project progresses.
So the next time a pewter- colored Sonoma pulls up to you
at a stoplight, make sure it doesn't have a TTS decal across
the windshield. Otherwise, it might send you home with your
tail between your legs.

The LS-1 V-8 was shoehorned into the Sonoma's engine compartment.
This engine, however, is outfitted with a Competition Cams
performance cam and a set of ported Lingenfelter heads. The
combination with special computer tuning by Steve Cole makes
430 hp.

The Sonoma also received some Street Scene treatments, including
a speed grille mounted in place of the factory piece.

The Sonoma can corner well too, averaging 0.85 g on a 200-foot
skidpad. The combination of Chassis Tech dropped spindles,
lower rear leaf springs, and Nitto tires really made a difference
in its cornering performance. Imagine what it would do with
a set of performance coil springs, shocks, and antisway bars!

The rear of the Sonoma was treated to the Street Scene Step
Savers, giving the truck a smoother appearance. A Gaylord's
tonneau cover was also painted the factory pewter to match
the rest of the truck.